The invention relates to a method and apparatus suitable for carding fibers.
The use of a carding machine to produce uniform webs of staple fibers, including natural fibers and synthetic fibers, by brushing the fibers and positioning the fibers more or less parallel to one another is well known in the art. When carding natural fibers such as cotton or wool, the carding process is also used to remove impurities from the fibers. While the carding process is a highly developed art, a number of problems still exist.
One of the main problems in any carding operation is the buildup of fibers on the journals of the various rolls. In addition to the main cylinder roll of a carding machine, there are worker and stripper rolls which, in conjunction with the main cylinder roll, brush and parallelize the fibers; a feed roll which feeds the fibers to the main cylinder roll; and a doffing roll which removes the combed and parallelized fibers from the main cylinder roll. Each of these rolls has a journaled axle and the buildup of fibers on and around the journals causes them to wear prematurely which in turn causes an increase in maintenance and costs of operation. While this is a serious problem when carding any type of fibers, processing polypropylene staple exacerbates the problem because of the tendency of this fiber to fuse on the journals and on the ends of the worker and stripper rolls. The fused polypropylene fibers form small hard particles which damage the wire or card cloth, and get into the carded web, resulting in a lower grade product.
An object of the present invention is to reduce the fiber buildup on the journals of a carding machine.
Another object of the invention is the elimination of small hard particles when carding polypropylene staple.
Still another object of the invention is an apparatus suitable for carrying out the above objects.